Universal pipe joint construction

Abstract

A universal joint construction connecting the ends of two pipes is formed by a pair of articulation rings, each fitted over the end portion of one of the pipes and attached thereto. A spherical convex outer surface on each articulation ring is engaged in opposite axial directions by a pair of concave inner surfaces - one on a joint or coupling pipe, and the other on a separation preventive ring attached to the joint pipe. A sealing member is provided between each pipe and articulation ring and between each joint pipe and articulation ring. For attachment, each of the articulation and separation preventive rings is provided with an internal annular groove receiving a split lock ring which is contracted to engage an external recess in the associated pipe by radially extending screws entering the groove at circumferentially spaced locations. The recess engaged by the lock ring attaching an articulation ring to one of the pipes can be made axially wider than the lock ring to permit relative axial movement at the joint.

I claim: 
     
       1. A universal pipe joint for connecting a pair of pipes comprising: a pair of articulation rings each having a spherical convex outer surface portion and a cylindrical inner surface portion adapted to fit over one of the pipes, and a sealing member interposed between each articulation ring and the pipe associated therewith;   means for attaching one of the articulation rings to each one of the pipes comprising an annular groove formed in the inner surface of the articulation ring, a first split lock ring adapted to fit in said groove, an annular recess formed in the outer surface of the pipe associated with such one articulation ring, and means for engaging the first lock ring in said recess by decreasing the diameter of the first lock ring;   a joint pipe having at each end thereof an annular concave inner surface adapted to engage a portion of the convex outer surface of one of the articulation rings, and a second sealing member interposed between the convex outer surface of each articulation ring and the joint pipe; and,   a pair of separation preventive rings, and means for attaching the separation preventive rings to the joint pipe at the ends thereof, each separation preventive ring having an annular concave inner surface which is adapted to engage a portion of the convex outer surface of one of the articulation rings in an axial direction opposite to the concave inner surface of the joint pipe engaging such one articulation ring.   
     
     
       2. A pipe joint as set forth in claim 1 wherein the articulation ring is provided with a cylindrical portion extending axially from the convex outer surface portion thereof, said annular groove is formed in said cylindrical portion, and said means for engaging the lock ring in said recess includes a plurality of radially extending screws spaced circumferentially around said cylindrical portion and engageable with said lock ring in said groove. 
     
     
       3. A pipe joint as set forth in claim 1 wherein said means for engaging the lock ring in said recess includes a plurality of circumferentially spaced threaded openings extending between said groove and the convex surface of the articulation ring, and headless screws adapted to be sunk within said threaded openings. 
     
     
       4. A pipe joint as set forth in claim 1 wherein said annular recess formed in the outer surface of the pipe has a greater width in the direction of the pipe axis than the lock ring, thereby permitting relative axial movement between the articulation ring and the pipe associated therewith. 
     
     
       5. A pipe joint as set forth in claim 1 wherein said means for attaching the separation preventive rings to the joint pipe comprises an inner cylindrical surface on each separation preventive ring adapted to fit over an outer cylindrical surface on the joint pipe, an annular groove formed in said inner cylindrical surface of the separation preventive ring, a second split lock ring adapted to fit in said groove, an annular recess formed in the outer cylindrical surface on the joint pipe, and means for engaging the second lock ring in said recess by decreasing the diameter of the second lock ring. 
     
     
       6. A pipe joint as set forth in claim 1 wherein said means for attaching the separation preventive rings to the joint pipe comprises an inner cylindrical surface on each separation preventive ring adapted to fit over an outer cylindrical surface on the joint pipe, an annular groove formed in said inner cylindrical surface of the separation preventive ring, a second split lock ring adapted to fit in said groove, an annular recess formed in the outer cylindrical surface on the joint pipe, and means for engaging the second lock ring in said recess by decreasing the diameter of the second lock ring. 
     
     
       7. A pipe joint as set forth in claim 1 wherein said concave inner surfaces of the joint pipe and one of the separation preventive rings which engage the convex outer surface of one of the articulation rings are spaced apart in the axial direction, and said second sealing member is located between such axially spaced concave inner surfaces.